Rotary eraser



March 16, 1937. D. A. DODSON ROTARY ERASER Filed March 14, 1956 lui'.

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Patented Mar. 16, 1937 UNITED STATES PATENT OFFICE 8 Claims.

Generically this invention relates to erasers, but it is more particularly directed to the type wherein a rotary motion is imparted to the eraser, during the erasing operation.

One of the principal objects of this invention is the provision of a rotary eraser of this character, having means for normally supporting the eraser element spaced above the matter to be erased and permitting it to Abe brought into approximate Contact with said matter before rotary movement thereof takes place.

Another important object of this invention is the provision of a rotary eraser of this character for erasing a typewritten letter or similar character comprising a guiding andsupporting element adapted to rest on the paper, exposing to View only the character to be erased, and permitting a clear view of such character except during the actual erasing movement of the device.

` 201 `A further important object of this invention is the provision of a rotary eraser having a supporting foot formed to expose the character to be erased and to cover the surface of the paper contiguous to and surrounding said character so that the erasable character only can be affected by the erasing operationvof the device and means for normally maintaining the erasing element above 'said foot to permit a clear view of said character during positioning of the device.

A further object of this invention is the provision of a rotary eraser having a supporting element, means in connection with the element for normally maintaining the eraser spaced above the paper on which the support rests and thereby permitting a Clearview of the character to be erased, and additional means for restricting the area to be erased, adapted to maintain the erasing surface of the eraser uniform throughout the erasing operation.

Another important object of this invention is the provision of Van eraser comprising a rotatable shaft terminating at one end in a chuck, a refill eraser holder for insertion in said chuck, and means for locking said holder therein.

A still further object of the invention is the provision of' a rotaryeraser including ascrew shaft and a cylindrical member mounted thereon and having lug means engageable in said screw,: a guideand supporting foot mounted on the opposite end of said shaft having means for `normally maintaining the eraser spaced above the 'paper andl foot supporting medium, whereby `downward movement of the cylindrical member brings the eraser in contact with the character to ,A be erased and then impart rotary movement thereto during the travel of said member throughout the entire length of said screw.

Fig. lis a side elevation of my improved eraser device.

Fig. 2 is a longitudinal section at right angles 5 to Fig. 1.

Fig. .3 is a cross section taken on the line 3-3 of Fig. 2.

Fig. 4 is a plan view of the blank from which the supporting member is formed. 10

Fig. 5 is a cross section on the line 5-5 of Fig. 2'. Y 1

Erasers of this general type with which I am familiar have proven decient in manyY respects, some of which are: that where an eraser restsv 15 on the paper it is diflicult to rotate thel same without damage to or tearing the paper, the normal position of the eraser preventing a clear vision of the character to be erased, diii'iculty in holding the device steady and in preventing the 20 eraser from contacting a greater surface area than that of the character to be erased, in some cases rotation of the eraser taking place before it has reached the surface to be erased, whereby such movement in one direction is exhausted 25 before effecting the erasure, and in other instances, the devices are of such complex construction as to cause the parts to quickly wear and to increase production and maintenance cost. 30

It was to overcome such deficiencies as above enumerated, and to provide a device of simple and inexpensive construction, comprising a supporting base or foot member perforated so as to be easily centered with respect to the character 35 to be erased and to overlie the surface surrounding such character, means for normally maintaining the eraser in such elevatedposition as to present a clear view of said character when the device is being operatively positioned with re- 40 spect thereto, a spring controlled cylinder housing including means coaoting with a spiral groove, whereby downward pressure on said cylinder moves the eraser to approximate contact with the paper and continued downward movement ef- 45 fects rotation of the eraser during the travel of said means throughout the full length of the screw, unique means forinserting and locking the refill eraser element in its holder and means in connection with said foot for shaping the cut- 50 ting surface of the eraser as well as restricting the erasing area, that I designed the device form.- ing the subject matter of this invention.

In the illustrated embodiment characterizing this invention there is shown a cylindrical or tu- 55 bular member A, rotatable rod or shaft B and support or base member C.

The cylinder A constituting the operating handle of the device is formed with a bottom cap I, adapted to frictionally engage over its lower end and, which if desired, may be threadedly or otherwise secured thereto. Said cap is perforated as at 2 to receive the rod or shaft B. Spirally wound on said rod or shaft and adjacent to its upper end is a metal strip 3 forming the helical groove or screw 4 and which is welded, soldered or otherwise suitably secured thereto, and while the screw is preferably formed as abovev described, it is understood that it may be formed in any other well known manner. A cap washer 5 is mounted on the upper end of shaft B formed with an upstanding crown portion 6 adapted to receive the upper end of said shaft. A cap 1 preferably of enlarged construction is frictionally or otherwise suitably mounted on the upper end of cylindrical member A and mounted intermediate said cap and washer 5 is a compression spring 8 adapted to normally maintain Said cylinder or handle A in extended position with respect to said screw 4. Suitably projecting in groove or screw 4 and integral with or suitably secured to the wall of cylinder A is lug 9, which is positioned to engage in the upper end of said groove 4 when handle A is in full normally extended position with respect to shaft B. Y

A support or base member C may be preferably formed from a one piece blank, stamped lout to form the blank D with the wing members I adapted to be curved and their meeting edges II soldered, welded or otherwise suitably united to form the tubular casing I2. The upper end portion I3 is folded on line I4 and soldered, Welded or otherwise suitably secured to the upper edges of casing I2 to form a closure therefor. The lower end portion I is cut on the line I6 and folded upwardly as at I'I and secured to the lower edges of casing I2 similar to end portion I3. Said ends I3 and I5 are respectively formed with openings I8 through which is adapted to extend rod or shaft B, and mounted on said shaft and within said casing I2 is a coil spring I9 and engaging the opposite ends of which are, in the present instance, cup washers 20. The lowermost washer is adapted to seat on end I5 and the upper washer on pin 2I or other suitable means carried by shaft B intermediate said Washer and the upper end I3 against which it is adapted to seat to limit the upward movement of said shaft under the action of spring I9, as will hereinafter more fully appear.

Stem portion 22 of blank D is bent at right angles on the line 23 to form the foot portion 24 formed with an opening 25, in alignment with openings I8 in the ends of said casing, said opening 25 being beveled as at 26 so that it will be of less diameter at its under surface and present a sharpened edge for a purpose directly more fully appearing.

A chuck or socket member 2'I is formed with a reduced portion 28 at its upper end which is adapted to engage over the lower end of shaft B to which it is secured by soldering, welding or any other suitable manner. Said chuck is formed at one side with a slot 29, adapted to receive the rib 30 formed on rell holder 3| in which is suitably secured an eraser element 32, when said holder is positioned in said chuck, so as to not only aid in retaining the holder therein but to prevent its rotary movement with respect thereto.

With further reference to coil spring I9, it will be apparent that this spring is of lesser tension than spring 8, so that pressure on handle A forces shaft B downwardly compressing spring I9 and bringing the eraser into approximate engagement with the paper or erasable character underlying foot 24, before compression of spring 8 and travel of lug 9 in screw 4 takes place causing rotation of eraser 32.

Although the operation of the device would seem to be clear from the above description, it might be well to further state that when it is desired to erase a pencil, ink or typewritten character or indicia and especially with reference to a typewritten letter or ligure expeditiously, without disarranging the paper in the machine, it is only necessary to place foot 24 on the paper with the erasable matter centered with respect to opening 25, and which may be easily accomplished by reason of the construction of the supporting member C' and the normally elevated position of the eraser 32, thereby permitting an unobstructed and clear view of the particular matter to be erased. When the device is thus positioned, downward pressure on handle A will cause said handle and shaft B to move downwardly as a unit against the action of spring I9 and guided by member C including aligned openings I8, when eraser 32 has reached or approximately reached opening 25 and paper 33 or other supporting medium for foot 24, continued downward movement of said handle effects compression of spring 8 and causes lug 9 to traverse screw 4 from its upper to its lower end effecting throughout such travel rotation of shaft B and eraser 32 within opening 25, thereby causing rotatable movement of said eraser and effecting erasement of said character. Upon release of the pressure on handle A, spring I9 returns said handle and shaft B to their initial elevated positions with respect to member C, and simultaneously spring 8 returns handle A to its normally extended position with respect to shaft B and reversing the travel of lug 9 with respect to screw 4 so that all of the movable parts are returned to their initial positions, and if a further application of the eraser to the erasable matter should be necessary, it is at once apparent, and the above operation may be repeated until the desired result is accomplished, and without the necessity of removing and repositioning the device as will be clear without further discussion.

From the above it will be apparent that I have designed a rotary eraser adapted to be easily positioned with respect to the matter to be erased,

permitting a clear view of such matter when the device is operatively positioned, designed to conne the view to the particular matter to be erased, permitting repeated operations without repositioning the device, said device comprising few parts, simple in construction, manufacturable at a minimum of cost, versatile in its adaptive use, and efcient for the purposes intended.

Although in practice I have found that the form of my invention illustrated in the accompanying drawing and referred to in the above description as the preferred embodiment, is the most eiiicient and practical; yet realizing the conditions concurrent with the adoption of my invention will necessarily vary, I desire to emphasize that various minor changes in details of construction, proportion and arrangement of parts, may be resorted to within the scope of the appended claims without departing from or sacrificing any of the principles of this invention. Having thus described my invention, what I desire protected by Letters Patent is as set forth in the following claims:

1. A rotary eraser comprising a shaft adapted to hold an eraser, means for supporting the shaft in a vertical plane and normally maintaining the. eraser spaced from the surface to be erased, said means including means coacting with the eraser and adapted to limit the operation of the eraser to a predetermined erasable area, means for slidably supporting aircasing on the upper end of said shaft and interacting means in connection with the casing for imparting a rotary movement to the shaft when moved longitudinally thereof..

2. A rotary eraser comprising a shaft, means mounted on one end of the shaft adapted to detachably hold an eraser, means for supporting the shaft in a vertical plane, means carried by said supporting means for normally maintaining the eraser spaced from the surface to be erased,V

additional means in connection with said suprporting means for centering said support with respect to the erasable matter co-acting with said surface and eraser and adapted to limit the operation of the eraser to the area defined by said centering means, means for slidably supporting a casing on the upper end of said shaft and interacting means in connection with the casing for imparting a rotary movement to the shaft when moved longitudinally thereof.

3. A rotary eraser comprising a shaft terminating at one end in chuck means, and eraser holding means mounted in said chuck, means detachably securing the eraser holding means in said chuck and preventing its rotationl with respect thereto, means for supporting the shaft in a vertical plane and normally maintaining the eraser spaced from the surface to be erased, said means including guide means coacting with said surface adapted to limit the operation of the eraser to the area defined by said guide means, means for slidably supporting a casing on the upper end of said shaft, and interacting means in connection with the casing for imparting a rotary movement to the shaft when moved longitudinally thereof. l

4. A rotary eraser comprising a shaft adapted to detachably hold an eraser at one end, means for supporting the shaft in a Vertical plane, said supporting means at one end adapted to embracingly support 'means for normally maintaining the eraser spaced from the surface to be erased, said means including at its free end guide means adapted to effect centering of the device with respect to the erasable matter and adapted to denne the area to be erased and to shape the erasing surface of the eraser corresponding to said area and maintain said surface constant throughout the life of the eraser.`

5. A rotary eraser comprising a shaft adapted at one end to hold a detachable eraser, means formed from a one piece blank for supporting the shaft in a vertical plane, said means including a guide means adapted to define the area to be erased and to shape the erasing surface of the eraser corresponding to said area, and additional means carried by said supporting means for normally maintaining the eraser spaced from said opening, means for slidably supporting a casing on the upper end of said shaft and interacting means in connection with the casing for imparting a rotary movement to the shaft when moved longitudinally thereof.

6. A rotary eraser comprising a shaft adapted to hold an eraser, means for supporting the shaft in a vertical plane and normally maintaining the eraser spaced from the surface to be erased, said means including guide means adapted to limit the operation of the eraser to the area defined by said sight means, means for slidably supporting a casing on the upper end of said shaft and interacting means in connection with the casing for imparting a rotary movement to the shaft when moved longitudinally thereof, under pressure in erasing direction, a spring mounted in the upper end of said casing for returning the same to its initial position upon release of said force, and a cap washer on the upper end of the shaft and forming a seat for said spring, whereby centering of said shaft with respect to said casing is effected and free rotation of the shaft permitted.

'7. A rotary eraser comprising'a shaft adapted to hold an eraser at its lower end, supporting means in connection with the lower end of the shaft, guide means adapted to limit the operation of the eraser to the area defined by said guide means, means for normally maintaining the eraser spaced from the surface to be erased and adapted to return the eraser to its initial position upon completion of the erasing operation, means for slidably supporting a casing on the upper end of said shaft, and interacting means in connection with the casing for imparting, a rotary movement to the shaft when moved longitudinally thereof.

8. A rotary eraser holder adapted to be supported by a surface containing erasable matter, comprising a shaft adapted to hold an eraser element at its lower end, a supporting means including foot means in connection with the lower end of the shaft, said foot means having a round opening substantially corresponding to the size of the eraser and adapted to limit the operation of the eraser to the area defined by said opening, means for normally maintaining the eraser spaced from the surface to be erased and adapted to return the eraser to its initial position upon completion of the erasing operation, means for slidably supporting a casing on the upper end of said shaft, and interacting means in connection with the casing for imparting a rotary movement to the shaft When moved longitudinally thereof.

DAVID A. DODSON. 

